Investigation on spin coated LLTO thin film nano-electrolytes for rechargeable lithium ion batteries

Abstract An attempt has been made to prepare Li 0.5 La 0.5 TiO 3 (LLTO) nano crystalline thin films on glass substrates by spin coating. Achievement of homogeneous thin films of LLTO without noticeable pinholes and cracks, with uniform morphology is a challenge and has been an impediment in the development of all solid state batteries which is addressed in the present work. The prepared uniform films calcined at 550 ° C for 5–20 - and 40 h, have been subjected to structural (XRD), optical (FTIR), morphological (SEM) and electrical (AC impedance) characterization. Complete phase transformation has been ensured by optimizing the duration of calcination of the films at 550 ° C for 40 h. Homogeneous films with uniform morphology, without any cracks and pin holes have been obtained on calcination at 550 ° C for 40 h. The overall ionic conductivity of the sample is obtained as 3.52×10 −7 S cm −1 for the film calcined over 40 h.